Hello -

I have been using a very simple procedure shown here written with Delphi 2010 to send emails to selected recipients using the Indy components which shipped with my D2010.  I am using hMailServer and the procedure works very well as written.  I have now decided to install a SSL certificate in hMail for encryption purposes and have gone through the certificate installation process and I have attached it to my mail ports.  When I run the procedure now the application locks up.  I can turn the problem on and 
off just by attaching or detaching the SSL certificate on my SMTP port in hMail.  I've tried various settings as I imagine there are some component properties which need modified in the IdSMTP or IdMessage components, and maybe some minor code alterations as well.  Thus far my fiddling has been unsuccessful.  If someone sees what I am missing, please sing out.  Thanks very much.   Mark   

{code}

procedure SendEmail;

begin

  Form1.IdMessage1.Clear;
  Form1.IdSMTP1.AuthType := satDefault; 
  Form1.IdSMTP1.Username := 'me@mydomain.com'; //AccountName;
  Form1.IdSMTP1.Password := 'abcdefgh'; //EMPassword;
  Form1.IdSMTP1.Host := 'mail.mydomain.com';  
  Form1.IdSMTP1.Port := 25;

  Form1.IdMessage1.From.Address := 'me@mydomain.com'; 
  Form1.IdMessage1.Recipients.EMailAddresses := 'you@yourdomain.com';
  Form1.IdMessage1.Subject := 'An interesting subject';
  Form1.IdMessage1.Body.Text := 'boorish drivel';

   try
     Form1.IdSMTP1.Connect;//(1000);
     Form1.IdSMTP1.Authenticate;
     Form1.IdSMTP1.Send(Form1.IdMessage1); //MailMessage
   finally
    if Form1.IdSMTP1.Connected then
      Form1.IdSMTP1.Disconnect;
    end;

end;
{code}

Mark wrote:

> When I run the procedure now the application locks up.

If you have not already done so, you need to:

1) assign an SSL IOHandler component, such as TIdSSLIOHandlerOpenSSL, to 
the TIdSMTP.IOHandler property, and configure it as needed (set the IOHandler.Method 
or IOHandler.SSLVersion property, at a mimimum).

2) set the TIdSMTP.UseTLS property to either utUseImplicitTLS or utUseExplicitTLS, 
depending on whether your SMTP server expects an SSL/TLS encryption handshake 
immediately upon connecting before any other data is exchanged (Implicit) 
or if it allows the client to connect unencrypted and send a STARTTLS command 
when it is ready to enable encryption (Explicit).

3) set the TIdSMTP.Port property to the server's SSL/TLS port (if the UseTLS 
property did not already set it to the correct value for you).  Implicit 
SSL uses port 465, whereas explicit TLS is typically done on port 587 but 
may also be supported on port 25.

--
Remy Lebeau (TeamB)

Thanks very much for the detailed response.  I will tackle this later this afternoon.

Mark

> {quote:title=Remy Lebeau (TeamB) wrote:}{quote}
> Mark wrote:
> 
> > When I run the procedure now the application locks up.
> 
> If you have not already done so, you need to:
> 
> 1) assign an SSL IOHandler component, such as TIdSSLIOHandlerOpenSSL, to 
> the TIdSMTP.IOHandler property, and configure it as needed (set the IOHandler.Method 
> or IOHandler.SSLVersion property, at a mimimum).
> 
> 2) set the TIdSMTP.UseTLS property to either utUseImplicitTLS or utUseExplicitTLS, 
> depending on whether your SMTP server expects an SSL/TLS encryption handshake 
> immediately upon connecting before any other data is exchanged (Implicit) 
> or if it allows the client to connect unencrypted and send a STARTTLS command 
> when it is ready to enable encryption (Explicit).
> 
> 3) set the TIdSMTP.Port property to the server's SSL/TLS port (if the UseTLS 
> property did not already set it to the correct value for you).  Implicit 
> SSL uses port 465, whereas explicit TLS is typically done on port 587 but 
> may also be supported on port 25.
> 
> --
> Remy Lebeau (TeamB)

Jumping in with both feet I have attempted to follow the guidance issued below (though I used TIdSSLIOHandlerSocketOpenSSL because I didn't see the TIdSSLIOHandlerOpenSSL as an available component).  I used many combinations of setup parameters for the Delphi code and the hMailServer settings, and while the program no longer locks up, I have not had success (as in receiving a test email).  In my search for information on hMailServer settings, I've come across information which leads me to believe I am not
 really following the best path for what I wish to accomplish.  I'll briefly reiterate my situation.

Using Delphi 2010 and Indy components I have created a simple send mail only (not necessary to have receive capability) email client to operate from within my application.  The client has always worked very well, and I call the sendmail procedure from my application, providing the appropriate recipient address to the procedure.  The recipients are located throughout the country and have typical email clients or have their company email addresses. I currently am not encrypting the contents of the message, 
and that is all I wish to do, just in case there is some personal information contained therein.  I only need a process to send a few emails per day, not receive, and my intent is to encrypt the contents during transmission. It occurs to me that the use of SSL may not be the answer.

If anyone can suggest an easy and effective method of encrypting simple 3 or 4 sentence messages, and then sending them to various email addresses through my Delphi application, please let me know.  Thank you.  Mark

> {quote:title=Remy Lebeau (TeamB) wrote:}{quote}
> Mark wrote:
> 
> > When I run the procedure now the application locks up.
> 
> If you have not already done so, you need to:
> 
> 1) assign an SSL IOHandler component, such as TIdSSLIOHandlerOpenSSL, to 
> the TIdSMTP.IOHandler property, and configure it as needed (set the IOHandler.Method 
> or IOHandler.SSLVersion property, at a mimimum).
> 
> 2) set the TIdSMTP.UseTLS property to either utUseImplicitTLS or utUseExplicitTLS, 
> depending on whether your SMTP server expects an SSL/TLS encryption handshake 
> immediately upon connecting before any other data is exchanged (Implicit) 
> or if it allows the client to connect unencrypted and send a STARTTLS command 
> when it is ready to enable encryption (Explicit).
> 
> 3) set the TIdSMTP.Port property to the server's SSL/TLS port (if the UseTLS 
> property did not already set it to the correct value for you).  Implicit 
> SSL uses port 465, whereas explicit TLS is typically done on port 587 but 
> may also be supported on port 25.
> 
> --
> Remy Lebeau (TeamB)

Mark Naples wrote:

>  It occurs to me that the use of SSL may not be the answer.

But SSL is exactly the answer (without resorting to manual
encryption/decryption of the email - meaning that the recipient will
need to run a program to decrypt the encrypted message).

Following is sample code that I use to send email via SSL in my
application (Using Delphi XE2, Latest version of Indy from daily
download site, Latest version of SSL Dlls ie
openssl-1.0.1c-i386-win32.zip):

[CODE]

unit Unit1;

interface

uses
  Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants,
  System.Classes, Vcl.Graphics,
  Vcl.Controls, Vcl.Forms, Vcl.Dialogs, IDMessage, IDSmtp, IdSSLOpenSSL,
  IdExplicitTLSClientServerBase, IDMessageBuilder, IdAntiFreezeBase,
  Vcl.StdCtrls;

type
  TForm1 = class(TForm)
    Button1: TButton;
    procedure Button1Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
    procedure SendEMail;
  end;

var
  Form1: TForm1;

implementation

{$R *.dfm}

procedure TForm1.Button1Click(Sender: TObject);
begin
  SendEMail;
end;

procedure TForm1.SendEMail;
var
  IDSMTP1: TIDSmtp;
  IdSSLIOHandlerSocketOpenSSL1: TIdSSLIOHandlerSocketOpenSSL;
  IDMessage1: TIDMessage;
  idMBHTML: TIdMessageBuilderHTML;
  stream: TMemoryStream;
  mesg: String;
  enc: TEncoding;
begin
  IDSMTP1 := TIDSmtp.Create;
  IdSSLIOHandlerSocketOpenSSL1 := TIdSSLIOHandlerSocketOpenSSL.Create;
  idMBHTML := TIdMessageBuilderHTML.Create;
  IDMessage1 := TIDMessage.Create;
  stream := TMemoryStream.Create;
  try
    with IDSMTP1 do
    begin
      Host := 'smtp.gmail.com';
      Port := 465;
      AuthType := satDefault;
      IOHandler := IdSSLIOHandlerSocketOpenSSL1;
      UseTLS := utUseImplicitTLS;

      Username := 'gfandango@gmail.com';
      Password := 'xxxxxxxxxxxxxxxxyz';
    end;

    mesg := 'The <u>Delphi Indy VCL component suite</u> is the
<b>best!</b>';
    stream.Write(mesg[1], Length(mesg) * SizeOf(Char));

    enc := nil;
    TEncoding.GetBufferEncoding(BytesOf(mesg), enc);

    with idMBHTML do
    begin
      stream.Position := 0;
      // HTML.LoadFromStream(stream, enc);
      PlainText.LoadFromStream(stream, enc);
      // Attachments.Add('FileName here');

      FillMessage(IDMessage1);
    end;

    with IDMessage1 do
    begin
      Subject := 'Test email';
      From.Address := 'gfandango@gmail.com';
      From.Name := 'Grim Fandango';
      Recipients.EMailAddresses := 'steve_goa@yahoo.com';
      // ReceiptRecipient.Address := '';
      // ReceiptRecipient.Name := '';
    end;

    with IDSMTP1 do
    begin
      if not Connected then
        Connect;
      Send(IDMessage1);
    end;

  finally
    stream.Free;
    IDMessage1.Free;
    idMBHTML.Free;
    IdSSLIOHandlerSocketOpenSSL1.Free;
    IDSMTP1.Free;
  end;

  ShowMessage('Email sent.');

end;

end.

[/CODE]




Please note that there is still something wrong with this code. In the
email that is received, I see only the first character of the message
ie 'T'. I'd appreciate if Remy would be so kind as to point out what is
wrong and how it can be fixed. TIA.


-- 
Steve Faleiro

Mark wrote:

> Jumping in with both feet I have attempted to follow the guidance issued 
below (though
> I used TIdSSLIOHandlerSocketOpenSSL because I didn't see the TIdSSLIOHandlerOpenSSL
> as an available component).

Yes, that is the correct component, sorry.

> I used many combinations of setup parameters for the Delphi code and the 
hMailServer settings

What EXACTLY did you try?

> while the program no longer locks up, I have not had success (as in receiving 
a test email).

You are able to call TIdSMTP.Send() without problem and TIdSMTP is not raising 
any exceptions then the emails are being sent correctly and it is the SMTP 
server's responsibility to deliver the messages to the recipients.  If the 
messages are not arriving in their inboxes then the SMTP server, not your 
app, is having delivery problems (bad recipients, fulll inboxes, network 
issues, etc).  Once your app has called TIdSMTP.Send() and it exited without 
exception, it is not your app's issue anymore.  Check the original sender's 
inbox to see if there are error messages being delivered explaining why your 
app's messages could not be delivered to the recipients.  That is how SMTP 
reports errors that occur after the initial SMTP transaction is complete.

> In my search for information on hMailServer settings, I've come across 
information which leads
> me to believe I am not really following the best path for what I wish to 
accomplish.

What EXACTLY did you read?

> I only need a process to send a few emails per day, not receive, and my 
intent
> is to encrypt the contents during transmission. It occurs to me that the 
use
> of SSL may not be the answer.

The only other option besides SSL is to encrypt the actual email contents 
itself before sending it to an SMTP server.  Indy does not support that option 
at this time, so you will have to encrypt the email yourself.

--
Remy Lebeau (TeamB)

Steve wrote:

> But SSL is exactly the answer (without resorting to manual
> encryption/decryption of the email - meaning that the recipient will
> need to run a program to decrypt the encrypted message).

Yes exactly.  SSL will encrypt the communication between your app and the 
receiving SMTP server, but the email itself will not be encrypted.  If you 
need that, that is completely separate from SMTP.

> Please note that there is still something wrong with this code. In the
> email that is received, I see only the first character of the message
> ie 'T'. I'd appreciate if Remy would be so kind as to point out what
> is wrong and how it can be fixed.

There are several problems with your code.

You are using TEncoding when you should not be at all, and you are using 
it wrong anyway.  Your use of TEncoding.GetBufferEncoding() will return TEncoding.Default 
because mesg is a UTF-16 encoded UnicodeString that does not have a UTF-16 
BOM in front of its data.

When you call PlainText.LoadFromStream(), you are passing it TEncoding.Default 
from TEncoding.GetBufferEncoding(), so it will interpret the stream contents 
incorrectly.  You should be using TEncoding.Unicode instead since the stream 
contents are UTF-16 encoded.

The correct thing to do is get rid of the use of the TMemoryStream and TEncoding 
completely, and let Indy handle encoding the data for you, by setting the 
MessageBuilder's PlainText/HTML and PlainTextCharSet/HTMLTextCharSet properties 
as needed, which will then set the TIdMessage's CharSet properties accordingly.

For example:

{code}
procedure TForm1.SendEMail;
var
  IdSMTP1: TIdSmtp;
  IdSSLIOHandlerSocketOpenSSL1: TIdSSLIOHandlerSocketOpenSSL;
  IdMessage1: TIDMessage;
  IdMBHTML: TIdMessageBuilderHTML;
  mesg: String;
begin
  IdSMTP1 := TIdSMTP.Create;
  IdSSLIOHandlerSocketOpenSSL1 := TIdSSLIOHandlerSocketOpenSSL.Create(IdSMTP1);
  IdMessage1 := TIdMessage.Create;
  try
    mesg := 'The <u>Delphi Indy VCL component suite</u> is the <b>best!</b>';

    IdMBHTML := TIdMessageBuilderHTML.Create;
    try
      with idMBHTML do
      begin
        // UTF-8 is more accepted on all platforms
        // let Indy convert the UTF-16 input data to UTF-8 for you...
        HTML.Text := mesg;
        HtmlCharSet := 'utf-8';
        // Attachments.Add('FileName here');
        FillMessage(IdMessage1);
      end;
    finally
      IdMBHTML.Free;
    end;

    with IdMessage1 do
    begin
      Subject := 'Test email';
      From.Address := 'gfandango@gmail.com';
      From.Name := 'Grim Fandango';
      Recipients.EMailAddresses := 'steve_goa@yahoo.com';
      // ReceiptRecipient.Address := '';
      // ReceiptRecipient.Name := '';
    end;

    with IdSMTP1 do
    begin
      Host := 'smtp.gmail.com';
      Port := 465;
      AuthType := satDefault;
      IOHandler := IdSSLIOHandlerSocketOpenSSL1;
      UseTLS := utUseImplicitTLS;
      Username := 'gfandango@gmail.com';
      Password := 'xxxxxxxxxxxxxxxxyz';

      Connect;
      try
        Send(IdMessage1);
      finally
        Disconnect;
      end;
    end;
  finally
    IdMessage1.Free;
    IdSMTP1.Free;
  end;

  ShowMessage('Email sent.');
end;
{code}

--
Remy Lebeau (TeamB)

Thanks much for your reply.   If I use gmail as the host do I need to establish a gmail account corresponding to the username shown in the code?  Mark

> {quote:title=Steve Faleiro wrote:}{quote}
> Mark Naples wrote:
> 
> >  It occurs to me that the use of SSL may not be the answer.
> 
> But SSL is exactly the answer (without resorting to manual
> encryption/decryption of the email - meaning that the recipient will
> need to run a program to decrypt the encrypted message).
> 
> Following is sample code that I use to send email via SSL in my
> application (Using Delphi XE2, Latest version of Indy from daily
> download site, Latest version of SSL Dlls ie
> openssl-1.0.1c-i386-win32.zip):
> 
> [CODE]
> 
> unit Unit1;
> 
> interface
> 
> uses
>   Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants,
>   System.Classes, Vcl.Graphics,
>   Vcl.Controls, Vcl.Forms, Vcl.Dialogs, IDMessage, IDSmtp, IdSSLOpenSSL,
>   IdExplicitTLSClientServerBase, IDMessageBuilder, IdAntiFreezeBase,
>   Vcl.StdCtrls;
> 
> type
>   TForm1 = class(TForm)
>     Button1: TButton;
>     procedure Button1Click(Sender: TObject);
>   private
>     { Private declarations }
>   public
>     { Public declarations }
>     procedure SendEMail;
>   end;
> 
> var
>   Form1: TForm1;
> 
> implementation
> 
> {$R *.dfm}
> 
> procedure TForm1.Button1Click(Sender: TObject);
> begin
>   SendEMail;
> end;
> 
> procedure TForm1.SendEMail;
> var
>   IDSMTP1: TIDSmtp;
>   IdSSLIOHandlerSocketOpenSSL1: TIdSSLIOHandlerSocketOpenSSL;
>   IDMessage1: TIDMessage;
>   idMBHTML: TIdMessageBuilderHTML;
>   stream: TMemoryStream;
>   mesg: String;
>   enc: TEncoding;
> begin
>   IDSMTP1 := TIDSmtp.Create;
>   IdSSLIOHandlerSocketOpenSSL1 := TIdSSLIOHandlerSocketOpenSSL.Create;
>   idMBHTML := TIdMessageBuilderHTML.Create;
>   IDMessage1 := TIDMessage.Create;
>   stream := TMemoryStream.Create;
>   try
>     with IDSMTP1 do
>     begin
>       Host := 'smtp.gmail.com';
>       Port := 465;
>       AuthType := satDefault;
>       IOHandler := IdSSLIOHandlerSocketOpenSSL1;
>       UseTLS := utUseImplicitTLS;
> 
>       Username := 'gfandango@gmail.com';
>       Password := 'xxxxxxxxxxxxxxxxyz';
>     end;
> 
>     mesg := 'The <u>Delphi Indy VCL component suite</u> is the
> <b>best!</b>';
>     stream.Write(mesg[1], Length(mesg) * SizeOf(Char));
> 
>     enc := nil;
>     TEncoding.GetBufferEncoding(BytesOf(mesg), enc);
> 
>     with idMBHTML do
>     begin
>       stream.Position := 0;
>       // HTML.LoadFromStream(stream, enc);
>       PlainText.LoadFromStream(stream, enc);
>       // Attachments.Add('FileName here');
> 
>       FillMessage(IDMessage1);
>     end;
> 
>     with IDMessage1 do
>     begin
>       Subject := 'Test email';
>       From.Address := 'gfandango@gmail.com';
>       From.Name := 'Grim Fandango';
>       Recipients.EMailAddresses := 'steve_goa@yahoo.com';
>       // ReceiptRecipient.Address := '';
>       // ReceiptRecipient.Name := '';
>     end;
> 
>     with IDSMTP1 do
>     begin
>       if not Connected then
>         Connect;
>       Send(IDMessage1);
>     end;
> 
>   finally
>     stream.Free;
>     IDMessage1.Free;
>     idMBHTML.Free;
>     IdSSLIOHandlerSocketOpenSSL1.Free;
>     IDSMTP1.Free;
>   end;
> 
>   ShowMessage('Email sent.');
> 
> end;
> 
> end.
> 
> [/CODE]
> 
> 
> 
> 
> Please note that there is still something wrong with this code. In the
> email that is received, I see only the first character of the message
> ie 'T'. I'd appreciate if Remy would be so kind as to point out what is
> wrong and how it can be fixed. TIA.
> 
> 
> -- 
> Steve Faleiro

Using your guidance from above I successfully transmitted emails from my application using the gmail host rather than hMailServer.  This will be my baseline process until such time as I successfully get the hMailServer working.  My sincere thanks.

You wrote above: "SSL will encrypt the communication between your app and the receiving SMTP server, but the email itself will not be encrypted."  I take that to mean that the contents of the message can not be seen anywhere along the transmission path from the time it is created by my application until the message arrives at the recipients mail server. This being the case, the weak link in the entire process comes down to any security shortcomings associated with the SMTP server of the recipient. If this
 is not an accurate description of the process feel free to set me straight.  Many thanks again.

Mark


> {quote:title=Remy Lebeau (TeamB) wrote:}{quote}
> Mark wrote:
> 
> > Jumping in with both feet I have attempted to follow the guidance issued 
> below (though
> > I used TIdSSLIOHandlerSocketOpenSSL because I didn't see the TIdSSLIOHandlerOpenSSL
> > as an available component).
> 
> Yes, that is the correct component, sorry.
> 
> > I used many combinations of setup parameters for the Delphi code and the 
> hMailServer settings
> 
> What EXACTLY did you try?
> 
> > while the program no longer locks up, I have not had success (as in receiving 
> a test email).
> 
> You are able to call TIdSMTP.Send() without problem and TIdSMTP is not raising 
> any exceptions then the emails are being sent correctly and it is the SMTP 
> server's responsibility to deliver the messages to the recipients.  If the 
> messages are not arriving in their inboxes then the SMTP server, not your 
> app, is having delivery problems (bad recipients, fulll inboxes, network 
> issues, etc).  Once your app has called TIdSMTP.Send() and it exited without 
> exception, it is not your app's issue anymore.  Check the original sender's 
> inbox to see if there are error messages being delivered explaining why your 
> app's messages could not be delivered to the recipients.  That is how SMTP 
> reports errors that occur after the initial SMTP transaction is complete.
> 
> > In my search for information on hMailServer settings, I've come across 
> information which leads
> > me to believe I am not really following the best path for what I wish to 
> accomplish.
> 
> What EXACTLY did you read?
> 
> > I only need a process to send a few emails per day, not receive, and my 
> intent
> > is to encrypt the contents during transmission. It occurs to me that the 
> use
> > of SSL may not be the answer.
> 
> The only other option besides SSL is to encrypt the actual email contents 
> itself before sending it to an SMTP server.  Indy does not support that option 
> at this time, so you will have to encrypt the email yourself.
> 
> --
> Remy Lebeau (TeamB)

Mark wrote:

> Thanks much for your reply.   If I use gmail as the host do I need to
> establish a gmail account corresponding to the username shown in the
> code?

If you want to send out emails using Gmail as the sending server, then yes. 
 But you can send emails to Gmail recipients without having your own Gmail 
account.

You could alternatively use TIdSMTPRelay instead of TIdSMTP.  That would 
make your app act like its own pseudo SMTP sending server.  It would connect 
directly to recipients' receiving SMTP servers, bypassing any intermediate 
SMTP servers.  The only requirement would be that you have to provide it 
with the IP/Host of a DNS server for it to use for its queries.

--
Remy Lebeau (TeamB)

Mark wrote:

> You wrote above: "SSL will encrypt the communication between your
> app and the receiving SMTP server, but the email itself will not be
> encrypted."  I take that to mean that the contents of the message
> can not be seen anywhere along the transmission path from the time
> it is created by my application until the message arrives at the recipients
> mail server.

No.  Only along the path between your app and the first SMTP server that 
your app is directly connected to.  Once that SMTP server has the email, 
it may pass it along to another SMTP server, and another, as needed until 
the email eventually reaches the recipient.  Each of those connections is 
outside of your app's control, and may or may not be SSL encrypted on their 
end.  If you want to ensure the privacy of the email along all transmission 
paths, you will have to encrypt the contents before giving it to the first 
server, and the recipient will have to decrypt it.

--
Remy Lebeau (TeamB)

I understand.  Given this information, is it worthwhile setting up the SSL for the purpose of ensuring privacy if it is a sure thing only on the first part of the journey?

Mark

> {quote:title=Remy Lebeau (TeamB) wrote:}{quote}
> Mark wrote:
> 
> > You wrote above: "SSL will encrypt the communication between your
> > app and the receiving SMTP server, but the email itself will not be
> > encrypted."  I take that to mean that the contents of the message
> > can not be seen anywhere along the transmission path from the time
> > it is created by my application until the message arrives at the recipients
> > mail server.
> 
> No.  Only along the path between your app and the first SMTP server that 
> your app is directly connected to.  Once that SMTP server has the email, 
> it may pass it along to another SMTP server, and another, as needed until 
> the email eventually reaches the recipient.  Each of those connections is 
> outside of your app's control, and may or may not be SSL encrypted on their 
> end.  If you want to ensure the privacy of the email along all transmission 
> paths, you will have to encrypt the contents before giving it to the first 
> server, and the recipient will have to decrypt it.
> 
> --
> Remy Lebeau (TeamB)

Mark wrote:

> I understand.  Given this information, is it worthwhile setting up the
> SSL for the purpose of ensuring privacy if it is a sure thing only on
> the first part of the journey?

That is really up to you to decide based on your needs.

--
Remy Lebeau (TeamB)

On 2012-08-13 16:20:37 -0400, Mark Naples <> said:

> I understand.  Given this information, is it worthwhile setting up the 
> SSL for the purpose of ensuring privacy if it is a sure thing only on 
> the first part of the journey?


The important privacy that the SSL connection gives you is the 
protection of your SMTP logon credentials (user id and password), which 
are often the same as your POP/IMAP credentials, so they are worth 
protecting.

Also, don't undervalue the privacy given by SSL between your mail 
client and the SMTP server.  Just run a traceroute to your SMTP server 
address and see how many servers your mail will pass through.  Though 
the SSL connection will not secure your message beyond that point, 
every little bit helps, IMO.

Of course, if the ultimate goal is to protect the contents of the 
e-mail from everyone other than the intended recipient, you will, as 
has been indicated, need to encrypt that email in a way that the 
recipient will be able to decrypt it.

I suggest using a known encryption library with plug-ins available for 
popular email clients so that you don't have to write something 
yourself for the recipients. Something based on PGP, such as OpenPGP, 
is probably a good bet.

--
Kevin Powick

Kevin wrote:

> The important privacy that the SSL connection gives you is the
> protection of your SMTP logon credentials (user id and password),
> which are often the same as your POP/IMAP credentials, so they are
> worth protecting.

Very true.  But even without SSL, credentials can still be protected via 
SASL if the server supports that (which most do), and that does not require 
SSL.  SSL encrypts the connection itself.  SASL hashes/encrypts just the 
credentials regardless of whether the connection is encrypted.

> Also, don't undervalue the privacy given by SSL between your mail
> client and the SMTP server.  Just run a traceroute to your SMTP
> server address and see how many servers your mail will pass through.

A traceroute will only show you how many servers a connection might pass 
through to reach that particular SMTP server (a different route might be 
used when establishing the real SMTP connection).  Once that SMTP server 
has the email, the email may have to hop through even more servers when it 
is delivered to recipients.  Traceroute will not show that leg of the journey.

--
Remy Lebeau (TeamB)

On 2012-08-13 22:03:21 -0400, Remy Lebeau (TeamB) <no.spam@no.spam.com> said:


> A traceroute will only show you how many servers a connection might pass
> through to reach that particular SMTP server (a different route might be
> used when establishing the real SMTP connection).

True.  I wasn't focusing on the specifics of internet communication; 
just trying to show that a connection from client to SMTP server was 
likely to involve many servers along the way.

> Once that SMTP server
> has the email, the email may have to hop through even more servers when it
> is delivered to recipients.
> Traceroute will not show that leg of the journey.

Yes, I believe that the part of my paragraph that you chose not to 
quote noted that SSL would not secure the message beyond the point of 
the SMTP server.

--
Kevin Powick

> {quote:title=Steve Faleiro wrote:}{quote}
> Mark Naples wrote:
> 
> >  It occurs to me that the use of SSL may not be the answer.
> 
> But SSL is exactly the answer (without resorting to manual
> encryption/decryption of the email - meaning that the recipient will
> need to run a program to decrypt the encrypted message).
> 
> Following is sample code that I use to send email via SSL in my
> application (Using Delphi XE2, Latest version of Indy from daily
> download site, Latest version of SSL Dlls ie
> openssl-1.0.1c-i386-win32.zip):
> 
> [CODE]
> 
> unit Unit1;
> 
> interface
> 
> uses
>   Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants,
>   System.Classes, Vcl.Graphics,
>   Vcl.Controls, Vcl.Forms, Vcl.Dialogs, IDMessage, IDSmtp, IdSSLOpenSSL,
>   IdExplicitTLSClientServerBase, IDMessageBuilder, IdAntiFreezeBase,
>   Vcl.StdCtrls;
> 
> type
>   TForm1 = class(TForm)
>     Button1: TButton;
>     procedure Button1Click(Sender: TObject);
>   private
>     { Private declarations }
>   public
>     { Public declarations }
>     procedure SendEMail;
>   end;
> 
> var
>   Form1: TForm1;
> 
> implementation
> 
> {$R *.dfm}
> 
> procedure TForm1.Button1Click(Sender: TObject);
> begin
>   SendEMail;
> end;
> 
> procedure TForm1.SendEMail;
> var
>   IDSMTP1: TIDSmtp;
>   IdSSLIOHandlerSocketOpenSSL1: TIdSSLIOHandlerSocketOpenSSL;
>   IDMessage1: TIDMessage;
>   idMBHTML: TIdMessageBuilderHTML;
>   stream: TMemoryStream;
>   mesg: String;
>   enc: TEncoding;
> begin
>   IDSMTP1 := TIDSmtp.Create;
>   IdSSLIOHandlerSocketOpenSSL1 := TIdSSLIOHandlerSocketOpenSSL.Create;
>   idMBHTML := TIdMessageBuilderHTML.Create;
>   IDMessage1 := TIDMessage.Create;
>   stream := TMemoryStream.Create;
>   try
>     with IDSMTP1 do
>     begin
>       Host := 'smtp.gmail.com';
>       Port := 465;
>       AuthType := satDefault;
>       IOHandler := IdSSLIOHandlerSocketOpenSSL1;
>       UseTLS := utUseImplicitTLS;
> 
>       Username := 'gfandango@gmail.com';
>       Password := 'xxxxxxxxxxxxxxxxyz';
>     end;
> 
>     mesg := 'The <u>Delphi Indy VCL component suite</u> is the
> <b>best!</b>';
>     stream.Write(mesg[1], Length(mesg) * SizeOf(Char));
> 
>     enc := nil;
>     TEncoding.GetBufferEncoding(BytesOf(mesg), enc);
> 
>     with idMBHTML do
>     begin
>       stream.Position := 0;
>       // HTML.LoadFromStream(stream, enc);
>       PlainText.LoadFromStream(stream, enc);
>       // Attachments.Add('FileName here');
> 
>       FillMessage(IDMessage1);
>     end;
> 
>     with IDMessage1 do
>     begin
>       Subject := 'Test email';
>       From.Address := 'gfandango@gmail.com';
>       From.Name := 'Grim Fandango';
>       Recipients.EMailAddresses := 'steve_goa@yahoo.com';
>       // ReceiptRecipient.Address := '';
>       // ReceiptRecipient.Name := '';
>     end;
> 
>     with IDSMTP1 do
>     begin
>       if not Connected then
>         Connect;
>       Send(IDMessage1);
>     end;
> 
>   finally
>     stream.Free;
>     IDMessage1.Free;
>     idMBHTML.Free;
>     IdSSLIOHandlerSocketOpenSSL1.Free;
>     IDSMTP1.Free;
>   end;
> 
>   ShowMessage('Email sent.');
> 
> end;
> 
> end.
> 
> [/CODE]
> 
> 
> 
> 
> Please note that there is still something wrong with this code. In the
> email that is received, I see only the first character of the message
> ie 'T'. I'd appreciate if Remy would be so kind as to point out what is
> wrong and how it can be fixed. TIA.
> 
> 
> -- 
> Steve Faleiro


I keep getting errors when trying to execute this code, first it says can't find SSL library then after I put that in the bin directory it says can't find vsinit.dll finally after I put that in bin it goes back to saying it can't find SSL library.  I have Delphi XE2 professional and can't seem to get this indy email thing to work no matter what.

Al wrote:

> I keep getting errors when trying to execute this code, first it says
> can't find SSL library

The standard OS search path for DLLs applies, unless you call Indy's IdOpenSSLSetLibPath() 
function to specify the exact folder that the OpenSSL DLLs reside in.

> then after I put that in the bin directory it says can't find vsinit.dll

Neither Indy nor OpenSSL use that DLL.

--
Remy Lebeau (TeamB)

>You could alternatively use TIdSMTPRelay instead of TIdSMTP.  That would 
>make your app act like its own pseudo SMTP sending server.  It would connect 
>directly to recipients' receiving SMTP servers, bypassing any intermediate 
>SMTP servers.  The only requirement would be that you have to provide it 
>with the IP/Host of a DNS server for it to use for its queries.

Is there any downside to that?  Any reason why using regular SMTP
server would be better in any common circumstances?

Paul wrote:

> Is there any downside to that?

Many SMTP servers restrict who can directly connect to them, to reduce spamming.

> Any reason why using regular SMTP server would be better in any common 
circumstances?

Legitimate SMTP servers tend to white-list each other, while providing validation 
of sending users to block known spammers.

--
Remy Lebeau (TeamB)

>Legitimate SMTP servers tend to white-list each other, while providing validation 
>of sending users to block known spammers.

Thanks.

This thread probably belongs in the Winsock group.  I tried using the
relay, and it didn't work and I don't think it was because of this
specific issue.  I'll post a separate post in the winsock group.